• failure of facial fusion is due to changes in the growth and morphogenesis of the facial prominences

• the lateral edge of the nasal pit flares outward instead of growing in toward the center and the maxillary prominence is projected laterally, preventing apposition and fusion of the facial prominences

• failure of facial fusion is due to changes in the growth and morphogenesis of the facial prominences

• the lateral edge of the nasal pit flares outward instead of growing in toward the center and the maxillary prominence is projected laterally, preventing apposition and fusion of the facial prominences